Crash when PersistentState size > signalr packet size

[davhdavh]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

Serializing too big value results in client error only, and the error has nothing to do with running out of size.

Expected Behavior

Server side log of "[PersistentState] failed to serialize due to exceeding max size" and no value stored so page generally works.

Steps To Reproduce

@page "/CrashMe"
@rendermode InteractiveServer

@code {

 [PersistentState] public string? Size { get; set; }

 protected override void OnInitialized()
 {
  Size ??=   new string(' ', 33000); //<-- adjust based on signalr size
  base.OnInitialized();
 }
}

Exceptions (if any)

{"LogLevel":"dbug","Category":"Microsoft.AspNetCore.Components.Infrastructure.PersistentStateValueProvider","Message":"Persisting value for storage key 'C785CK8khNb/Sy/a6SCdBFMSQz/+6HiZ+JrFnc1a+cE=' of type 'String' from component 'CrashMe' for property 'Size'","TraceID":"bee41b484c25b49d17d5bb2119d2ae06","SpanID":"397e4dfbacff334b","Timestamp":"2025-09-16T04:18:51.3539421Z"}
{"LogLevel":"dbug","Category":"Microsoft.AspNetCore.Components.Infrastructure.PersistentStateValueProvider","Message":"Persisting value for storage key '9lBB97fs0JtFcROKh5YEUEUbwrXZBG1ttURT0f9Cpr8=' of type 'Nullable`1' from component 'CrashMe' for property 'Id'","TraceID":"bee41b484c25b49d17d5bb2119d2ae06","SpanID":"397e4dfbacff334b","Timestamp":"2025-09-16T04:18:51.3543959Z"}
{"LogLevel":"dbug","Category":"Microsoft.AspNetCore.Components.Server.Circuits.CircuitRegistry","Message":"Attempting to disconnect circuit with id WzlubqEnxk0AyKTsDUAny6Mo4p8SXtxrpibQPvMQ8jE from connection czHJ5ep4MuaYsra_o9hJLg.","TraceID":"7c8015de96fea12cda59c7269924465d","SpanID":"83f1b1487be301af","Timestamp":"2025-09-16T04:18:51.4691385Z"}

Navigated to https://localhost:7226/CrashMe
blazor.web.4n3g7fqvoz.js:1 [2025-09-16T04:22:32.216Z] Information: Normalizing '_blazor' to 'https://localhost:7226/_blazor'.
blazor.web.4n3g7fqvoz.js:1 [2025-09-16T04:22:32.239Z] Information: WebSocket connected to wss://localhost:7226/_blazor?id=bN4lFf8dAuz9xu-wJvoqAQ.
blazor.web.4n3g7fqvoz.js:1  [2025-09-16T04:22:32.288Z] Error: Connection disconnected with error 'Error: Server returned an error on close: Connection closed with an error.'.
log @ blazor.web.4n3g7fqvoz.js:1
_stopConnection @ blazor.web.4n3g7fqvoz.js:1
features.reconnect.transport.onclose @ blazor.web.4n3g7fqvoz.js:1
_close @ blazor.web.4n3g7fqvoz.js:1
stop @ blazor.web.4n3g7fqvoz.js:1
_stopInternal @ blazor.web.4n3g7fqvoz.js:1
await in _stopInternal
stop @ blazor.web.4n3g7fqvoz.js:1
_processIncomingData @ blazor.web.4n3g7fqvoz.js:1
Cn.connection.onreceive @ blazor.web.4n3g7fqvoz.js:1
i.onmessage @ blazor.web.4n3g7fqvoz.js:1


blazor.web.4n3g7fqvoz.js:1  Uncaught (in promise) Error: Server returned an error on close: Connection closed with an error.
    at Cn._processIncomingData (blazor.web.4n3g7fqvoz.js:1:66670)
    at Cn.connection.onreceive (blazor.web.4n3g7fqvoz.js:1:59835)
    at i.onmessage (blazor.web.4n3g7fqvoz.js:1:83928)
_processIncomingData @ blazor.web.4n3g7fqvoz.js:1
Cn.connection.onreceive @ blazor.web.4n3g7fqvoz.js:1
i.onmessage @ blazor.web.4n3g7fqvoz.js:1

.NET Version

10.0.100-rc.1.25451.107

Anything else?

No response

[MihuBot]

I'm a bot. Here is a possible related and/or duplicate issue (I may be wrong):

• PersistentComponentState: large state will crash the client, unable to recover #44935

[javiercn]

@davhdavh thanks for contacting us.

This is a dupe of #44935

In general, for any state persisted to the client the server limits apply. In this case the SignalR message size. So this is by design and our recommendations are:

• Limit the amount of data that you put in persistent component state.
• Raise the SignalR message size to accommodate it to your needs.

We don't have a way of knowing that the SignalR message size is.

I thought we had an issue for revisiting our dependence on the SignalR message size, but I see now that we don't, so I've filed to track improvements in this area explicitly #63693